Dealers receive the stop-sale order in an email on Thursday. So far, no recall has been issued on cars already sold.
Usually, such orders are given to address some safety issue. Stop-sale orders mean dealers must do something to the vehicles before they can be sold.
The move comes just a month after GM recalled 1.6 million older compact cars to fix an ignition switch problem linked to 31 crashes and 12 deaths.
GM has acknowledged it knew about the problem for at least a decade but did not recall the cars until last month.